Pneumatic for keyboard musical instruments.



R. H. MQHARDY. PNEUMATIC FOR KEYBOARD MUSICAL INSTRUMENTS.

APPLICATION FILED NOV. 5, 1907.

' FER- ili- PATENTED AUG. 4, 1908.

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cated in the central wall.

, there arr-er araaaatscoer RUDQQL-PH HERMANN MCHVARDY, or LONDON, ENGLAND.

PNEUMATIC FOR KEYBOARD MUSICAL INSTRUMFINTS.

To all whom it may concern:

Be it knownthat I, RUDOLPH HERMANN MCHARDY,'a subject of'the King of Great Britain and Ireland, residing at London,

England, have invented a certain new and useful Improvement in Pneumatics for Keyboard Musical Instruments, of which the following is a specification. p

This invention relates to pneumatics for use inmechanically-operated keyboard musical instrument such as automatic pianos.

The object of the invention is to effect cer. tain improvements in the construction of such neumatics to the ends that the part-s fbr can bemanufactured and assembled quickly and at small cost, that the comleted pneumaticsshall give reliable, uniorm and eflicient operation, and that the pneumatics for an nstrument may be so compactly arranged as to occupy but'small I s Q In accordance with the invention, the neumatics are built in pairs, each pair havmg a common, central wall and two movable walls one on either side of the common wall and connected thereto by the usual flexible covering, the two pneumatics being adapted to be collapsed and inflated independently and their movable walls being connected to independent keys of the inStrument- The valves controlling the entrance and exit of air to and from the double pneumatic are lo By this arrangement of the parts, the pneumatics for an instrument can be socompactly arranged as to occupy little space within the casing; thus, with this construction of pneumatic, auto matic operating mechanism may be installed within an upright piano of the usual type without any change in the casing thereof.

The )referred embodiment of the inven tion is illustrated in the accompanying drawin s, in which I i ure 1 is a section through one of the doub e pneumatics; Fi 2 is a similar view broken away in part, illustrating one of the v a valves; lug. 3 18 a transverse section on line 3-3 of Fig. 1 Fig. 4 is a transverse section on line 44 of Fig. 2; and Fig. 5 is a detail View hereinafter referred to. I

Referring to these drawings, the suctionor vacuum-chest of the instrument is-shown at 1, this chest consisting of a long box of rectangular cross-section" extending the length of the'instrument and connected to I the air-pump by which air is exhausted Specification of Letters Pate ntas Application filed November t, 1907. Sa a No. 400,888.

Patented Aug. 4, 1908.

therefrom. Thepneumatics may be mounted upon this chest and are shown as so su ported in the drawings. Each of the doub l pneumatics consists of a common central wall 2 and two movable walls 3 and 4 hinged to opposite sides of the central wall. Coverings 5 of flexible material, such as kid, are secured to the edges of the'central and'movable walls in the usual manner, these coverings will fold readily when the neumatics are connected by suitable rods with independent .keys of the instrument, the wall 4 being rod 6 and the wall 3 by a rod 7 through a pivoted lever 8, this arrangement of the rods being ado ted in order that the pneumatics may be r isposed in a horizontal position.

in order to secure a compact arrangement of the parts, the valves controlling theentrance and exit of air to and from the pneumatics are arranged within the central wall 2 of the double pneumatic. For this purpose, wall 2 is formed in two .parts as shown in the along. one side, preferably by employing a piece of textile fabric 9 pasted to the-adjacent edges of the two pieces. Within each of the two parts of the central wall 2 is a valve for controlling the passage of air to one of the pneumatics and a valve-operating means con-.rolling the operation of the valve in the other part of the central wall. As shown in Figs. 1, 2 and 3 the adjacent faces of the two parts of wall 2 are cut away through a portion of their'length so as to form an opening 10 when the two parts are brought together, which opening is adapted for connection with the suction-chamber 1. The construction of each of the valves is bestshown in Fig. from which it will be seen circular opening 12 cut therein, communicating with the passage 10 and two openings 13 and 14 leading from the opening 12, one to the outer face of the part 11 (that is, to the interior of the pneumatic), and the other to the side of the part-11 (that is, to the atmos-. phere). Within the opening 12, is a valve 15,

thin leather secured to opposite faces thereof and a stem 16 projecting u )wardly therefrom and loosely connected with the valve 15. metallic annulus 17 is securedupon the part 1 11, partially closing the opening 12. The

shown as connected directly with a key by a" drawings, these parts being hinged together UNITED 'EEaPeT mcellapsed. The movable wa ls 3 and 4 are that the part 11 of ,the central wall Z'has a 1 consisting of a disk of fiber having disks of i 65 being creased as shown in Fig. 3, so that they I inner edge of this annulus is provided with a narrow l'lange, as shown in Fig; 2, adapted for coaction with the valve 15. The stem 16 of the v alvc projects through the opening in the annulus 17 for coaction with the valve-operating means. in order to preventexcessive lateral movement of valve 15 in the opening 12, a guard 1h" (Fig. 5) is provided, consist ing preferably of a wire bent to form a circular portion at the center thereof, through which the stem 16 projects, and downwardly turned ends which may be driven into the material of the part 11. The circular portion formed in the wire 18 is considerably larger than the stem 16 of the valve, so that it does not form a bearing for the stem, but merely precludes lateral movement of the valve 15 in opening 12 to such extent that the operation of the valve will not be uniform and reliable The opening 12 may be quickly formed by a suitable machine. and its depth accurately gaged, and the valve 15 and annulus 17, constructed as above described, may be readily made of the exact thickness desired, so that provision for adjustment of the parts of the valve is rendered unnecessary.

The valve 15 in the position in which it is shown in Fig. 2 permits air to be drawn from the penumatic through the passage 13, opening 12 and passage into the suction-chamber 1. When the valve is raised, it coat-ts with the llange on the inner edge of the annulus 17 to close this passage and to open a path for the air through passage 14, opening 12 and passage 13 to the pneumatic.

The valve 15 is operated by a pull of ordinary construction located upon the other part 18 of the central wall 2. This part 18 an opening 19 therethrough, to which the null 20 is connected, this pull having a strip 21 of stiller material secured thereto in position to coact wit-h the end of stem 16. The valve for controlling the )neumaticon the outer face of the part 18 is located within the part 18 in an opening 22 (Fig. 1) formed therein. This valve is operated by a pull' 23 located on the part 11 of the wall 2 and supplied with air through a passage 24 leading through the part 11.

Means are provided for connecting the pulls 2t) and 23 with openings on the tracker. board. ln the drawings, 1 have shown devices for this purpose which are also used for supporting the double pneumatic upon the suctionchest 1. These consist of hollow s rews 25 extending through openings in the walls of the suction-chest, their ends entering threaded openings in the parts 11 and is of illc central wall 2 and communicating with the passages 2-1 and ll) respectively.

To the outer ends of these screws, flexible pipes 26 are connected, these pipes leading to and openings on the Irackcr-bllard-in the unal The pull s 2t) and 23 are normally collapsed,

due to the fact that a very small opening is formed in the. tubular n' embers 25 within the suction-chambel 1. When pull 2!) is collapsed, the valve 15 is drawn to the upper position by the suction thereon and atmospheric pressure under the val\e,15 and the pneumatic on the outer face of wall 11 is therefore connected with the atmosphere through passages 13, 12 and 1-1, and is disconnected from the suction-box bv the coaction of valve 15 with annulus 17. When the music-roll, moving over the tracker board, permits air to enter pipe 27, the pull' 20 is expanded and moves the valve 15 downwardl v until its lower lace bears on the bottom of the opening 12 and its upper face is separated from the flange-on the annulus 17. The connection of the pneumatic to the atmosphere is thus closed and the air in the pneumatic is quickly withdrawn therefrom through passages 13, 12 and 10 to the suction-box. This results in collapsing the pneumatic and operating the key of the instrument, as will be well ni'iderstood.

it will be seen that in this manner a very compact arrangementol the parts is obtained, the two pneumatics being very thin, so that a single tier of them only is required to operate an upright piano. (,xreater compactness and protection ol" the delicate parts is obtained by placing the valves and their actlating devices within the central wall of the double pneumatic. Furthermore, the construction is such that the pneumatics may be manufactured at very small cost, particularly no delicate adjustment of any of the parts is required.

Having now described my invention, what I claim as new therein and desire to secure by Letters Patent is as follows 1* 1. In a keyboard musical instrument, a pair of pneumatics having a common wall, two movable walls located one on cilherside of said common wall, and valve mechanism controlling the air supply of said pneumatics ,located within said common wall, keys, and

connections between said movable \Yull-H and independent keys of the instrument. substantially as set forth.

2. In a keyboard musical instrument, a pair of pneumatics having a common wall, two movable walls located one on either side of said common wall, two valves each controlling the passage of air to and from one of said pneumatics, and an operating device for each of said valves, said valves and operating devices being located within said common wall, keys, and connections between said movable walls and independent keys of the instrument, substantially as set forth.

3. in a keyboard musical instrument, a pair of pneumaticshaving a common wall formed in two parts secured Logetliei', two movable walls located one on either side of: said comn'lon wall, a valve located in each of sense? said parts of the central wall controllin githe passage of air to and from one of said pneu matics, =and a pneumatic device oneach of said parts'for operating thevalve on the other part, keys, and connections between aid-movable walls and independent keys of thefinstrument, substantially as set forth.

4. In a keyboard-musical instrument, the combination of a suction-chamber, a pair of piieumatics havinga common wall and two I m ovabie walls one on either side of said common wall, two valves located Within the com mon wall, passagesl'formed 1n sald common wall leading from each of said "valves to the suction-chamber, the atmosphere and oil "of said gpneumatics, keys, and connections/betweeneald movable wallsfand Jndependent keys of the instrument,substantially as set;

:forth.

'lirakeyboarcl musical instrument, the combination of asuct on-chamber, a palr-of' pneumatics having a coxnliion wall formed of l two parts secured together and two'fmovalile walls one on either sxde of said common wall, two valves located-Jone in each of said parts of the common wall, a passage leading from the suction-chamber to saidvalves, assages formed in each of said parts leadmgi'rom the partaipassages for carrying air to said de- V1088, eys, and connections between sald movable Walls and independent keys of the instrument, substantially as set forth. 6. In a keyboard musical instrument, a support, a pneumatic, a pneumatically-actuated valve for said pneumatic, a hollow screw -for securing thepneumatic to said support, a

connection to one end of said screw l or carrymg air thereto, and aconnectlon between then other end of said screwand the actuating devices of said valve, substai'itially as set forth.

7. In a keyboard musical instrument, a

pair of pneumatics having a connnon wall and two movable walls one on either S1(l 6 of said common wall, an opening in said central Wall, a metallic annulus partially closing said opening, a valve movable between the bottom of said opening and said annulus, a guide valye therein 'to the pneumatic adjacent l thereto and to the atmosphere, a pneumatic i valve-actuating device located in each of said This specification signed and witnessed this 29th day of October, i907.

RUDOLPH HERMANN MCHARDY.

Witnesses:

D. S. EDMONDS,

I. McINTosn. 

